The present invention relates primarily to the inter-connection and physical arrangement of multiple personal computers (PCs), and more specifically to any collection of PCs that require network interconnections.
The development of the PC in the late 1970s ushered in a new chapter in the development of computing. Prior to the introduction of the PC mainframe and minicomputers were primarily used for computing needs. Such mainframe and minicomputers implement a Centralized Processing model using a centralized processor. The PC was, and remains, a complete, stand alone computer designed for use by one person. The PC, at the time of its introduction, had few, if any, physical or data security features, had no means of communicating effectively with other computers, had very little data storage capacity, and except for the simplest programs, was under-powered. However, since its introduction, PC technology has greatly improved. In the early 1980s the first PC network was introduced, and that network of PCs created both the distributed processor and the distributed processing computer models.
As networking technology improved, means were developed to connect PCs and engineering workstations that employed different computer architectures and operating systems, and as a result, networks of PCs and engineering workstations increasingly grew in size. Bridges and routers were introduced that allowed data traffic to flow from one network to another. Hubs and concentrators were introduced that allowed individual networks to further increase in size, so that today Local Area Networks (LANs) and Wide Area Networks (WANs) are highly complex installations that can span the globe. However, the basic building block of these networks remains the PC. Even though the PC has been vastly improved, having greater speed and power and significantly greater storage capacity, PCs remain, essentially, a stand alone computer with little, if any, physical or data security features, except for those imposed by a Network Operating System (NOS).
As the PC and networking technology improved, many of the applications that were once performed on mainframe and minicomputers began to migrate to networks of PCs in a process called downsizing or rightsizing. This process was enabled by the continuing improvements in PC and networking technology and the introduction of new software models such as client-server computing. However, the driving force behind downsizing is cost. The aggregate processing power and storage capacity of a small to medium-sized network of PCs may easily exceed all but the most powerful super computers, at a significantly lower cost. With software technology in place, organizations would like to continue the process of downsizing. However, organizations are reluctant to entrust their mission-critical applications to networks that do not have the physical or data security, or the reliability, that they are accustomed to in the mainframe or minicomputer environments.
Another trend in the fast moving computing industry is the increasing use of graphically intensive applications, the increasing use of sound, and the use of multimedia applications. This trend further increases the need for better performance, improved reliability, easier system management, reduced maintenance, greater security, and reduced cost of ownership.
The concept of interconnecting a plurality of personal computers is, of course, not new. Personal computer networks were introduced only a few years after the introduction of the PC. Nor is the concept of centralizing computing resources, which has long been the standard for the mainframe and minicomputer environments. However, at present no successful attempt has been made to centralize the computing resources of a network of PCs. There are PC systems currently in use that provide connections between a number of workstation consisting of a monitor, keyboard, and mouse, and a single PC. These workstations all share the single CPU in the PC. While these systems may appear to be distributed processing systems they are, in fact, a single centralized processor, similar to the mainframe and mini-computer computing model.
There are also systems currently in use that separate workstation elements from the balance of the PC. These systems use a combination of digital and analog technology to transmit the video signals (analog) from the graphics adapter in the PC system unit to the workstation, and the keyboard and mouse information (digital) from the workstation to the PC system unit. Essentially these systems use signal conditioning and amplifications to drive these signals over much greater distances than allowed by the length of the monitor, keyboard and mouse cable supplied with a standard PC. The nature and makeup of these signals, though, is the same as those carried by standard monitor, keyboard and mouse cables supplied with a standard PC.
While such systems provide a means of separating workstation and computer elements, they suffer from a number of limitations. These limitations include the need for a large number of conductors in a shielded cable. The cost of this type of cable, and the cost of the terminations for this type of cable, are considerably higher than the cost of a standard Ethernet compatible unshielded twisted pair or fiber optic cables.
Another limitation of the current art is flexibility. The type of systems described above are designed for a specific combination of workstation elements. These elements may be a monochrome monitor and keyboard, or a color monitor, keyboard, and mouse. Any change in the specified peripheral devices attached to the workstation, such as the addition of a floppy drive, CD-ROM, or printer, for example, will require a different design using additional conductors in transmission cables.
Further, systems which merely separate workstation elements from the balance of the PC suffer from a number of additional limitations, aside from the inefficient and cumbersome data transmission system described above. The centrally placed computers must share certain resources, such as floppy and CD-ROM drives, rather than having those devices available at the workstations for the exclusive use of the end users.
Other systems allow date transmission between a workstation and a remotely located computer server. Such systems suffer from a number of limitations, aside from inefficient and cumbersome data transmission system. System resources are not centralized. In fact they are further disbursed by the addition of new components at the workstations, the server computers and somewhere in between, further reducing reliability and security. All of the normal networked computers remain as fully standalone computers, connected to the field installed network.
The above described limitations, and others, are overcome by the present invention, which centralizes all computing resources, except for the workstations, and provides a highly managed switch that provides a number of additional functions, while dramatically improving reliability, performance, maintainability, and security and reducing total cost of ownership.
Accordingly, the present invention provides a computer system with a plurality of computer workstations and corresponding computer modules. The computer workstations each have a monitor, an input device, and a workstation transmission adaptor. The computer workstations each also have a first portion of a video display adaptor. The computer workstations do not have a processor forming a central processing unit, but instead, the corresponding computer modules contain such a processor. In addition to processors, each of the computer modules have short term memory and long term storage connected to the processors, as well as a second portion of a video display adaptor connected to the processor and a module transmission adaptor connected to the second portion of the video display adaptor in the processor. A plurality of cables connect the module network adaptors and the workstation network adaptors.
In one embodiment, the first portion of the video display adaptor comprises a RAM digital to analog converter connected to the monitor, a graphics RAM, and a graphics accelerator connected to the workstation network adaptor. Such an embodiment of the second portion of the video display adaptor comprises a bus interface connected to a driver connected to a bus interface connected to the processor and a module network adaptor, the driver being adapted for converting graphics commands from the processor and do graphics commands for interpretation by the graphics accelerator.
In one embodiment there is a distributed computer system having centrally available processing units. A plurality of computer workstations are connected to a plurality of processing units by computer transmission cables. In one embodiment each of the workstations may be connected to any of the plurality of processing units. These connections are accomplished by a switching unit controlled by a management computer where the management computer automatically connects and disconnects individual computer workstations to individual processing units. In a typical embodiment, there are more computer workstations then processing units and the management computer disconnects idle computer workstations from processing units and connects previously idle computer workstations that become active to processing units not then connected to another computer workstation. A portion of a video display adapter is included in computer workstations while a second portion of a video display adapter is included in the processing units.
Further objects, features, and advantages of the invention will become apparent from the following detailed description taken in conjunction with accompanying drawings showing illustrative embodiments of the invention which like parts are designated by like reference numerals throughout.